Maryland
Attorney General Douglas F. Gansler today applauded two Supreme
Court decisions
issued today in which state and environmental
petitioners prevailed
in two important air pollution cases—one involving EPA’s authority
to regulate greenhouse gas emissions from motor vehicles, and the other involving
the appropriate emissions test for determining when modifications to existing
power plants and other industrial facilities trigger a requirement to install
state-of-the-art pollution control equipment affecting greenhouse gas emissions.
In the first case, Massachusetts v. EPA, the United States Supreme Court rejected
EPA’s arguments that it does not have the authority to regulate greenhouse
gas emissions, and that even if it did have the authority, it had properly refused
to exercise its authority. In a 5 to 4 decision, the Court ruled that the Clean
Air Act clearly authorizes regulation of greenhouse gas emissions and that EPA’s
determination not to regulate such emissions was based on impermissible considerations
under the Clean Air Act.

In the second near
unanimous decision, Environmental Defense v. Duke Energy, the
Supreme Court reversed the 4th Circuit Court
of Appeals decision and held that upgrades or other modifications
to existing power plants or other industrial facilities are subject
to Clean Air Act permit provisions requiring installation of best
available control technology when the modifications result in annual
emissions increases, regardless of whether there is an hourly emission
rate increase. The court rejected the Fourth Circuit Court’s
view that the permit requirement applies only if the modification
results in an hourly increase in emissions. Maryland applies an
annual emissions test, which subjects more upgrades to the permit
requirements, and thus, is more protective of health and the environment.

“Today’s Supreme Court decisions are an important
victory for the states,” said Attorney General Gansler. “For
years, states have taken the lead in enforcing environmental laws
in the absence of a strong federal partner. We strongly encourage
the EPA to do its job and regulate greenhouse gas emissions from
automobiles and require utilities to install state-of-the-art pollution
controls.”

Maryland participated as an amicus along with other states in
support of the state and environmental petitioners.